Watercraft



April 4, 1939. E. B; w LF 2,152,983

' I WATERCRAFT Fired Aug. 5, 1934 3 Sheets-Sheet 2 Wind Abeam Before 77w Wm) April 3 E. B. WILFOIQD 2,152,983

I I WATERCRAFT Filed Aug. 5, 1954 s Shets-Sheet 3 Auto Bord!) v0 Compozzerz t Axis Of Hotatzorz llcsultuzt fibre-e INVENTOR. EDWARD BURKE WILFORD Patented Apr. .4, 1939 UNITED STATES- PATENT OFFICE 2,152,983 WATERCRAFT Edward Burke Wilford, Mei-ion, Pa. Application August 3, 1934, Serial No. 738,219

invention consists of watercraft comprising any suitable hollow or buoyant supporting structure or hull, upon which is mounted, upon any suitable stationary mast or superstructure or the like, a propeller-like rotor having certain aerodynamic characteristics, and bearing a certain relationship to the hull, whereby it may most effectively utilize the forces of wind under all op-.

erating conditions.

My invention further consists of other novel features of construction which will appear more fully from the following detailed description.

For the purpose of illustrating my invention, I have shown in the accompanying drawings, forms thereof which are at present preferred by me,

since the same have been found in practice to give satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized, and that my invention is not limited to the precise arrangement and organization of the instrumentalities as herein shown and described.

Referring to the drawings, in which like reference characters indicate like parts, Figure 1 represents a side elevational view, of the craft embodying my invention, shown in a more orless diagrammatic manner;

Figure 2 represents an end elevational view or the same; Figure 3 represents a side elevational view of the rotor hub and control;

Figure 4 represents a front elevational view of the rotorhub and control, wlth the blade shown partly broken away;' Figures 5, 6 and 7 represent diagrammatic or schematic top plan'viewsof the water-craft embodylng my invention, illustrating three different operating conditions, and corresponding settings of the rotor most effectively to meet these operating conditions;

Figure 8 represents a more or less diagrammatic frontielevational view of a modified form also shown diagrammatically.

Figure 10 represents a vector analysisshowing the development of the tractive or propulsive force.

In carrying out my invention I provide either a single hull of any suitable type, such as the hull 5 I0 indicated in Figures 1 to 7 inclusive, or dual hulls II and [2, indicated in Figures 8 and 9, suitably connected by the structure l3.

A mast or other supporting superstructure I4 is mounted in a generally upright position in the 10 hull, preferably slightly in advance of the longitudinal center of the hull, and is rotatably mounted in suitable bearing or supporting struc-- ture [5, so that it may be rotated at the will of the operator by means of any suitable handle l6, l5 firmly connected with the mast .I4. I may mount the mast M in suitable anti-friction bearings, including anti-friction thrust-bearings, to support the vertical load, so that the mast may more readily be turned. 20

To the top of the mast a stationary rotor pivot or axle I1 is secured by any suitable means, such as the member l8; the axis of the rotor pivot being arranged at a slight angle to the horizontal, as indicated more particularly in Figure 3 25 of the drawings. To the outer end of the rotor pivot I! the generally tubular rotor hub I9 is rotatably secured by means of a ball-bearing or other anti-friction bearings 20 and 2!, and is retained in place by a suitable lock-nut or re- 30 taining nut 22. The hub l9 carries a plurality (four illustrated in the drawings) of equidistantly spaced and generally radial rotor blade sockets 23, in which are journalled the rotor blade pivots or spars 24, which carry, and which 35 are a part of, the blades 25, of suitably cambered cross-section and of suitable construction. The rotor pivots or spars 2! are also preferably-mounted in anti-friction bearings 26 and 21, capable of taking both radial as well as axial loads; it being 40 understood that the bearing constructions here shown are merely schematic illustrations, as no claim is made to the particular details of bearing construction, as any conventional bearing construction suitable for the purpose may be 45 employed. The rotor blade sockets 23 are preferably also interconnected with each other by means of bracing members 28, and braced to the hub by means of brace members 29 and II.

To the inner ends of the rotor blade pivots 24, 50

" similar deflecting arms or pitch control arms ii are secured, having follower projections or pins 32 extending into the annular groove 33 of a; collar ll, slidably mounted upon the rotor pivot I! (or axial movement, and pinned thereto by movement relative thereto. The pin 35 extends through a slot 36 in the rotor pivot. The rotor pivot is hollow, as indicated by the dotted lines 31, and the central portion of the pin 35 is connected through a link 38 to one arm of the bellcrank rocker arm 39, which is pivoted to the pivot I! at 40. The other arm of the bell-crank rocker arm is connected through a suitable link 4| to a control lever 42, pivoted at 43 on the mast I4. By this means, the upward and downward deflection of the pitch control lever 42 will correspondingly and uniformly vary the pitch of the rotor blades 25.

Any suitable brake drum 44 may be connected to the hub 19, whereby the rotational motion of the rotor may be arrested when it is desired to render the same inoperative. This may be effected by any suitable brake shoe or brake band surrounding, or disposed in operative relation to, the brake drum, and having suitable manually operable connections for causing the brake shoe orband toact upon the brake drum. As any conventional form of brake drum or brake shoe or band, suitable for the mechanism, may be employed, the details of this have .also not been fully developed in the drawings.

At the stern or aft part of the hall I provide any suitable rudder 41, having any suitable manual control 48 within reach of the operator.

The pitch of the rotor blades is maintained within such small angles to the plane of the rotor, and the disc or'plane of the rotor is so inclined to the vertical and horizontal, that while the wind acting against the rotor as a whole (the forces of the wind being assumed generally to lie on a horizontal plane) will develop a forward component in all operating conditions, except possibly in a dead into-wind'position, a further component upon the individual bladeswill cause the blades to rotate about the hub axis in such a direction that the pitch of the blades will be so related to the rotational direction of the rotor as to cause the rotor to develop propulsive force upon its supporting pivot, wholly as a result of its rotation and pitch, which will be in the same general direction as the forward component of the wind' on the rotor disc area as a whole. This relationship of rotor blade pitch angle to the 'wind direction or air-flow direction is generally referred to in aeronautics as auto-rotation".

In actual operation the rudder 41 is used to compensate for the transverse, or side component of the reactional forces in a manner similar to the manner in which a rudder would be used in connection with a sail.

means of the cross-pin 35, against rotational The advantage of my present construction is that the wind forces can be utilized with a higher degree of efficiency under all operating conditions, and the craft can be headed more nearly into the wind and maneuvered more readily.

In Figure 10 I have illustrated a vector analysis a of the wind forces upon a blade of the rotor which blade in this diagrammatic illustration is viewed enclwise from the top. Thus, it will be seen that the wind velocity indicated in the diagram gives rise to a relative wind velocitybetween blade and wind (on one side of the rotor)\. which is in excess of the wind velocity and which in turn produces a lift" or propulsive force in a forward direction which is then utilized for propelling the craft, and which also produces an autorotative component which serves to keep the rotor in rotation.

A center board 49 may also be provided for further resisting any sidewise displacement of the hull structure.

I am aware that my invention may be embodied in other specific forms without departingfrom the spirit or essential attributes thereof, and I therefore desire the present embodiments to be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to' indicate the scope of the invention.

Having thus described my invention, what I' hereby claim as new and desire to secure by Letters Patent, is:

- 1. A watercraft comprising a hull, a generally upright mast carried by the hull, a rotor comprising a hub structure, a plurality of blades and means mounting the blades with the longitudinal axis of each blade in substantially rigid relation with the axis of the hub structure, means mounting the rotor on the mast for auto-rotation in a plane which makes an acute angle with the axis of the mast, and means for uniformly and simultaneously varying the pitch of all of said rotor blades.

2. A watercraft comprising a hull, a genera upright mast carried by the hull, a rotor comprising a hub structure, a plurality of blades and means mounting the blades with the longitudinal axis of each blade in substantially rigid relation with the axis of the hub structure, means mounting the hub on the mastfor auto-rotation of the rotor in an approximately vertical plane, and means operable at will for uniformly and simultaneously varying the pitch of all of said rotor blades.

EDWARD BURKE WI'LFORD. 55 

